Coax Gaining As Home-Network Backbone

Networking audio, high-definition video and data over a home's existing coaxial cables is becoming a reality with the introduction of two competing technologies by Coaxsys and Entropic Communications.

Adapters offered by Coaxsys to the custom installation market turn a home's coaxial cable jacks into Ethernet ports to connect Internet Protocol (IP)-enabled audio-video devices, PCs and broadband modems without sacrificing cable TV or satellite TV service. The company is also marketing its technology to local phone companies that want to offer Internet Protocol TV (IPTV) to their customers over DSL lines.

For its part, San Diego-based Entropic announced availability of c.LINK-technology-equipped chips that can be embedded in CE and PC products to deliver network capability. The technology, which the Multimedia over Coax Alliance (MoCA) plans to incorporate in a standard due in the first quarter, is being deployed by one Japanese cable network, Jupiter Telecommunications, in Panasonic network products designed to distribute broadband access over a multiple dwelling unit's coaxial cables.

Both technologies can be used to deliver DVR- and server-based audio and video to TVs and audio systems throughout the house, deliver broadband-data access to multiple rooms, and eliminate the need to rewire a house with CAT-5 cables. Both also work with coax cable networks incorporating one or more signal splitters.

Coaxys also positions its proprietary technology as allowing telephone companies to distribute DSL-based IPTV services through a home's existing coaxial cable. In this application, IPTV service would use up a coaxial cable's bandwidth, leaving no room for satellite- or cable-TV programming, Coaxsys said. The company's technology, however, will enable cable-TV and satellite-TV services to coexist on the same cables with broadband access and other IP-based applications, such as IP-based media servers and IP-based security cameras, with quality of service (QoS).

Coaxsys is targeting custom install channels for the first time with TVnet Ethernet-over-coax adapters that plug into RG-6 and RG-59 cable, eliminating the need to run new wires in retrofit installs. A single "master adapter" can distribute IP signals to up to eight target adapters connected to A/V systems in a home. Each adapter is priced at a suggested $199.

Any IP-enabled PC or A/V device, including Ethernet-equipped A/V servers and DVRs, can be connected to an adapter. Throughput is 95Mbps from master to target and 76Mbps from target to target. Using MPEG-2 compression, up to four HD streams can be delivered simultaneously on one network, and MPEG-4 compression would deliver more than 10, the company said.

Coaxsys adapters have been deployed by more than 50 small telephone companies, cable operators and other service providers. The technology is also available to set-top box and semiconductor companies to make their products TVnet-ready, the company said.

For its part, Entropic's 270Mbps technology, in MoCA field testing, has consistently delivered more than 100Mbps of usable throughput in real-world conditions to 95 percent of the coax jacks in test homes, the alliance said.

It's said to incorporate high QoS, the security of a wired connection and state-of-the-art packet-level encryption.

MoCA taps "the vast amount of unused bandwidth available on coaxial cables" to "deliver multiple simultaneous streams of HD- and DVD-quality digital entertainment and high-speed data to consumers without glitches or freezes," the group contended.

The IP-based standard will enable PC and A/V networks to coexist on the same coax-cable infrastructure in a home. The standard's bandwidth will enable multiple PCs to share a broadband cable modem connection while multiple streams of HDTV are distributed throughout the house. MoCA can also be used to distribute premium cable channels, pay-per-view channels and DVR content over coax to TVs connected to small clients.

In addition, MoCA networks could double as the wired backbone for a wireless UWB (ultrawideband) network, and they could distribute IP-based TV programming streamed from the Internet.